ASTM C1057-22

SIGNIFICANCE AND USE 5.1 The procedures in this practice support the determination of the burn hazard potential for a heated surface. These procedures provide an estimate of the maximum skin contact temperature and must be used in conjunction with Guide C1055 to evaluate the surface hazard potential. 5.2 The two procedures outlined herein are both based upon the same heat transfer principles. Method A uses a mathematical model to predict the contact temperature, while Method B uses a plastic rubber probe having similar heat transfer characteristics to the human finger to “measure” the contact temperature on real systems. 5.3 These procedures serve as an estimate for the skin contact temperatures which might occur for the “average” individual. Unusual conditions of exposure, incorrect design assumptions, subject health conditions, or unforeseen operating conditions will potentially negate the validity of the estimations. 5.4 These procedures are limited to direct contact exposure only. Conditions of personal exposure to periods of high ambient temperatures, direct flame exposure, or high radiant fluxes will potentially cause human injury in periods other than determined herein. Evaluation of exposures other than direct contact are beyond the scope of this practice. 5.5 Cold Surface Exposure—No consensus criteria exists for the destruction of skin cells by freezing. If, at some future time, such criteria are developed, extrapolation of the techniques presented here will serve as a basis for cold surface exposure evaluation. SCOPE 1.1 This practice covers a procedure for evaluating the skin contact temperature for heated surfaces. Two complimentary procedures are presented. The first is a purely mathematical approximation that is used during design or for worst case evaluation. The second method describes the thermesthesiometer, an instrument that analogues the human sensory mechanism and is only used on operating systems. Note 1: Both procedures listed herein are intended for use with Guide C1055. When used in conjunction with that guide, these procedures can determine the burn hazard potential for a heated surface. 1.2 A bibliography of human burn evaluation studies and surface hazard measurement is provided in the References at the end of Guide C1055. Thermesthesiometer and mathematical modeling references are provided in the References at the end of this practice (1-5).2 1.3 This practice addresses the skin contact temperature determination for passive heated surfaces only. The analysis procedures contained herein are not applicable to chemical, electrical, or other similar hazards that provide a heat generation source at the location of contact. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.